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Introduction Poly(vinylidene fluoride) (PVDF) has received great attention as a membrane material with regard to its outstanding properties,i.e.high mechanical strength, thermal stability, chemical resistance, as compared with otherpolymeric materials.
Additional organic materials that canimprove PVDF membrane properties include polymethy acrylate (PMA) [6,7], polyvinyl acetate (PVAC) [8], and cellulose acetate (CA) [9].The addition of organic hydrophilicmaterials can improve some properties of membranes, but reducesmembrane strength.
And the effect ofthe 1, 2 - propylene glycol contentand coagulation bath temperature on properties and structure of PVDF membranes was investigated.
Mechanical Properties Measurement.
The membrane thickness is determined by the phase separation process, which is mostly dominated by two factors, i.e. thermodynamics and kinetics.

Long-term effects of these factors may change the physical properties of the insulator, which may affect its thermal insulating properties.
Physico-mechanical properties and chemical mineralogical compositions of cements are shown in table 2-4.
Physical and mechanical properties of cement used in specimen Compressive strength compression/bending, [MPa] in 28 days Curing period, [min].
Currently, the most effective and simple way to improve the physical-mechanical properties of cement solutions and concrete is through the use of chemical additives.
When additives are introduced, the technical properties of the concrete mixture, the hardening processes of the concrete itself and its operational properties change substantially.

Introduction Magnesium and its alloys have excellent physical and mechanical properties for a number of applications [1,2].
It generally applies that the silicides of metals and non-metals have outstanding anticorrosion properties.
The present paper addresses the question of research in the preparation of silicon layers by the WSP-H 500© plasma spraying system, the effect of such parameters like a feeding distance (FD), the structure of layers and the measurement of the layers properties by electrochemical impedance spectroscopy.
The feeding distance affects the pre-heating temperature of silicon powder and the improvement of adhesive properties of silicon plasma coatings.
The interpretation of the measurement results from the electrochemical impedance spectroscopy is difficult for plasma coatings and there are plenty of factors affecting the result.

To obtain mechanical properties concerning the base and welded metals, a series of creep and tensile tests were conducted at 600 ºC, and creep crack growth tests were also performed under different applied loads using 1/2" compact tension specimens at 600 ºC.
The selection of the G91 steel is based primarily on its low thermal expansion coefficient and high resistance to stress corrosion cracking in water/steam systems compared to austenitic stainless steels, and also has better mechanical properties at elevated temperatures compared to alternate 2.25Cr-1Mo steel [1-3].
After welding, morphologies of the welded block were observed for the BM, WM and heat affect zone (HAZ) regions.
To obtain material properties used in C* equation, the tensile, creep and CCG tests were performed for the BM and the WM of the G91 steel.
Results and Discussion Material properties.

The local similarity of numerical value properties is calculated using the Eq. 1
(1) Where, sim(x, y) is the local similarity, x and y are the values of properties.
The local similarity of fuzzy logic value properties is calculated using the Eq. 2.
(3) Where, M is the largest value of the properties.
The result is the parameters that take into account all the existing restrictive factors.

The structural properties such as interlayer bonding state and fatigue performance were evaluated.
Overall, ERS material and structure had excellent road performance and mechanical properties.
While A:B=1: 2.3 and 1: 2.8, tensile properties met the requirements.
It can be filled more binder to improve the mix flexibility and anti-aging properties.
Fatigue Properties.

Tab.1 presents the mechanical properties of gabion in the field test.
This is because the simulation has ignored the effects of filling compacting during the construction and other unforeseen factors.
The simulation is always idealized, while the actual construction is affected by many factors such as compactness of filling and many other parameters.
The vertical earth pressure is affected by the grade of wall surface, stiffness of wall surface, film effect of wire and geo-synthetics, compaction of filling and many other factors.
The distribution of vertical earth pressure is closely related to the tensile and uplift safety factor of geo-synthetics.

Besides, these factors also result in shifting the Ni content of the NiTi matrix phase to higher values [3,4].
It attained better mechanical properties with ductilities (>7%), large recovery strain (>6%) and Young’s modulus closed to human bone (15-25 GPa).
A study of varying the Ar pressure only improved the mechanical properties and not for the porosity effect as it achieved with 10-16 vol% [25].
P.Stöver, D. (2006a), Improvement of Mechanical Properties of Powder Metallurgical NiTi Shape Memory Alloy, Adv.
P. (2009aSpace-holder engineered porous NiTi shape memory alloys with improved pore characteristics and mechanical properties). 474(1-2): L1-L5

Stability of the Jeffcott Rotor with Local Rubbing He LI1,a, Xiaozhe CHEN1,b, Bangchun WEN1,c 1School of Mechanical Engineering and Automation, Northeastern University, Shenyang, China.
Suppose that k is stiffness of rotor shaft, m is mass, c is bearing damping factor, kr is stator radial stiffness, u is eccentric distance, w is angle frequency of rotor , and ignore the effect of gravity, so that the motion differential equation of local rubbing of Jeffcott rotor system are given by (3) Inducing transformation non-dimension: Motion differential equations of local rubbing of Jeffcott rotor system with non-dimension are as follows: (4) In addition, letting , and just taking account for autonomous system, Eq. 4 is transformed into (5) Where ,, ,
In addition to the clearance and the stiffness ratio b, the system damping and friction coefficient are also important factors affecting rotor stability.
Analysis on vibration properties of rotor rubbing.

Ontology technology can be used to express various parameters factors that affect tree growth management, and develop resource domain ontology standardization of tree growth management.
The content of resource information of tree growth management are many, which includes the selection, optimization of operating measures and technology, and the decision-making of efficiency, they are decided by factors such as long cycle of tree growth and resource management, complex influencing factors and diverse business objectives, the economic benefits of tree growth management decisions has been the major object of tree growth, and it has a broad research base from the perspective of theory and practice.
The ontology of tree growth resource management decision-making consists of concepts, properties, axioms and instances.
Resource information engine needs the support of the resource information database, the exiting knowledge ontology of agricultural science and technology literature are used to construct the tree growth management resource ontology, the decision-making ontology based on the waterfall model which is built by ontology, then establish standardized tree growth management resources knowledge conceptual system, determine the various logical relationship between the concept and provide prerequisites for the properties for tree growth management organizations as well as the construction of growth model of the resource information of tree.
The growth simulation of tree mainly performs qualitative observations of different growth conditions and stages, then judges the growth mode, determines the overall framework of the morphology of description, measures the tree topology, geometry, mechanical properties, extracts the tree morphology rules model based on the growth rules, and simulate trees growth, finally establishes tree growth model based on a variety of competitive factors.